Hook: Daiichi 1730 bent shank nymph hook #8-10
Thread: to match body
Body: gray rabbit fur (still on the skin)
Weight: lead wire
Spines: two short pieces of stiff, heavy monofilament
Wing: two whole, gray marabou feathers.
Wrap lead wire along the back portion of the hook (from the bend to the rear) and secure with thread and head cement. Tie in the two pieces of stiff mono just on the eye side of the bend and angle them forward and down in a V-shape. Wrap the rabbit fur for the body. Tie in two whole marabou feathers flat over the body. Finish with a thread head and head cement. Note that there are lots of possible modifications. I often use crystal chenille rather than rabbit fur for the body. Spines can be added to almost any fly that sits hook point up on the bottom such as crayfish imitations.
[see LaFontaine, Gary. Trout Flies (Proven Patterns). Greycliff, 1993. for more detail.]